Features
  • 4.0 inch, Kapton former, edge wound aluminium voice coil
  • 280W continuous program power handling
  • Frequency range: 500Hz - 20kHz
  • 4-slot optimized geometry phase plug
  • Titanium diaphragm, Polyimide surround

The ND940 is a ultra compact size, high performance, high power handling 4.0-inch diaphragm compression driver with a 1.4 inch exit throat. A thin copper ring is precision pressed on to the pole piece in order to modify and lower the inductance characteristics of the magnetic circuit and voice coil providing a controlled extension of the acoustic frequency response. The voice coil assembly is designed using a high strength, high temperature Kapton® voice coil former and edge wound copper clad aluminium wire directly joined to the diaphragm by RCF proprietary Direct Drive kapton technology. The ND940 features a 4-slot, optimised geometry, phase plug design. Extended computer assisted mathematical modelling and testing has resulted in a geometry that provides a balanced acoustic performance controlling and lowering air distortion and maximizing output.

Part number:

15100012
ND940 16 OHM
16ohm

15129053
ND940
8ohm

Specifications
General specifications
Exit Throat Diameter
1.4 inch / 36 mm
Related Impedance
8 ohm
Program Power (watt)
280 W
Power handling capacity
140 W
Sensitivity
110 dB
Frequency range
500 - 20000 Hz
Suspension Design
Flat
Minimum Impedance (ohm)
8.50 ohm
Voice Coil Diameter
4.0 inch / 102 mm
Voice Coil Former Design
Direct Drive Kapton
Number of layers
1
Kind of layers
outside
Flux Density
2.0 T
Phase Plug Design
4 slot
Thiele - small parameters
Bl factor (Bl) (T x m)
17.60 T x m
Mounting information
Overall diameter
140 mm / 5.51 inches
Overall height
60 mm / 2.36 inches
Mounting
4 x 6 mm threaded holes at 90°
Standard compliance
Safety agency
CE compliant
Size
Weight
2.72 kg / 6 lbs
Shipping information
Package Height
79 mm / 3.11 inches
Package Width
169 mm / 6.65 inches
Package Depth
171 mm / 6.73 inches
Package Weight
2.87 kg / 6.33 lbs
Downloads
SPECSHEETS
PDF
988 KB
19-02-2024
DRAWINGS
DXF
2.1 MB
22-01-2024
PDF
339 KB
22-01-2024
ZIP
1.7 MB
22-01-2024